Immune responses of patients without cancer recurrence after a cancer vaccine over a long term

Abstract

The present study aimed to clarify the humoral and cellular immune responses of patients with cancer who experienced no recurrence over a long term after receiving a cancer vaccine. The immune kinetics were investigated in response to a personalized peptide vaccination (PPV) among 44 Japanese patients without an active tumor at entry to the vaccination: Lung adenocarcinoma (n=11); colon (n=18); and breast cancer (n=15) (9, 10, 12, 8 and 5 patients with stage I, II, III and IV recurrences, respectively). The patients' immunoglobulin G (IgG) and cytotoxic T lymphocyte (CTL) activities were measured using a multiplexed Luminex assay and an interferon-γ release assay, respectively. There were no severe adverse events related to the PPV other than a grade III injection site reaction. A potent boost in IgG or CTL at the end of the 1st vaccination cycle was observed in 77% of the patients (n=84). The IgG levels were sustained throughout the follow-up period, whereas the CTL levels declined and were transient. A total of 37 of the 44 patients (84%) had no recurrence, with a median follow-up of 67.6 months (interquartile range, 45.6-82.8 months). Overall, the PPV induced long-term humoral immunity with transient cellular immunity in the majority of patients with cancer without an active tumor at their entry to the PPV.

Long-term efficacy of the peptide-based COVID-19 T cell activator CoVac-1 in healthy adults

“…The titers of these peptide-specific IgG antibodies correlated with intensity of CoVac-1-induced T cell responses, indicating that the potent CoVac-1-specific CD4 + T cell responses support induction of B cells (33). CoVac-1-specific antibody titers occurred mostly around day 56, peaked at month 6 and month 3 for P5_mem and P6_ORF8, respectively, and persisted until month 12, thereby exhibiting kinetics similar to those observed after peptide-based vaccination in cancer and other infectious diseases (34,35). This underlines the importance of the careful selection of the CoVac-1 peptides from non-surface viral proteins as well as from buried (or hidden) amino acid sequences, which are not accessible for antibodies in their conformational state, to avoid the risk for vaccine-associated disease enhancement (15).…”

Exploring the Potential of Humoral Immune Response to Commensal Bifidobacterium as a Biomarker for Human Health, including Both Malignant and Non-Malignant Diseases: A Perspective on Detection Strategies and Future Directions

“…In our previous studies, we reported a compelling correlation between the levels of antibodies against CTL epitopes in pre-vaccination plasma and extended overall survival in multiple clinical studies for various types of cancer patients [17,25,65]. Furthermore, our investigations unveiled the presence of these humoral immune responses to CTL epitope peptides in the blood of both unvaccinated cancer patients and unvaccinated healthy donors, with notably higher detectable levels in younger generations [10][11][12]16,17,65] (Table 1). We also reported that immune boosting in both cellular and humoral responses with cancer vaccines using CTL epitope peptides was well correlated with overall survival with a hazard ratio of 0.2 (95% CI, 0.06-0.73; log-rank p = 0.0239) [48,66].…”

“…Since then, thousands of genes and their respective antibody-recognized tumor antigen peptides have been determined using SEREX methods [8,9]. Over the past 30 years, researchers have identified large numbers of genes and tumor antigens recognized by the mechanisms of specific immunity [7][8][9][10][11][12][13][14][15][16][17]. Those determinations have enabled us to better understand the nature of tumor-associated antigens (TAAs) recognized by the cellular and humoral immune system.…”